Hey,

I think I may have screwed up somewhere. I have replaced my spark plugs and now the Service Engine Soon light flashes and the engine runs really rough. Anyone have any ideas?

 

Not knowing what year we are dealing with, or what engine, I'd suggest making sure you didn't inadvertantly knock off any wire connectors and/or vaccum hoses.

 

Oh yea, sorry

02 Chevy Blazer V6 Vortec

Checked the plug wires and they seem to be connected well.

 

Make sure you put the wires on right. Thats what it sounds like.

 

I did them one at a time to make sure I put them back on right. Could I have cracked a plug putting it in, or is it more likely that I didn't put a wire on correctly

 

It could be a cracked spark plug but very unlikely unless you tighted them down WAY to tight. It sounds like the wires are messed up, make sure they are all connected. It might also be the spark plugs arent gapped right.

 

Ok, I will recheck the connections. The spark plugs were supposed to be pre-gapped from the factory. They are Bosch Platinum.

 

NEVER EVER trust pre-gapped plugs...it only takes a second to check them...and I agree with 93LT, check all the harnesses and vaccum lines, I don't think a plug wire should throw a code. Oh, and take out those junk plugs and put in some AC Delcos... the tips of the Bosch plugs have been known to break off from the plug overheating...from experience

 

I wasn't talking about the plug wires, but rather the other wiring connectors to various sensors and such.